Process of fermenting wort.



PATENTED SEPT. 25, 1906.

H. A. SGHALK. PROCESS OF FERMENTING WQRT.

APPLIUATION FILED APR. 17, 1906.

I ATEN'I UFFIGE.

HERMANN A. SCHALK, OF NEXV YORK, N. Y.

PROCESS OF FERIVIENTING WORT- Specification of Letters Patent.

Patented Sept. 25, 1906.

Application filed p i 1'7, 1906. Serial No. 312,107.

To all whom it may concern:

Be it known that I, I'IER-MANN A. SOIIALK, a citizen of the UnitedStates, residing at New York city,Manhattan, county and State of NewYork, have invented new and useful Improvements in Processes ofFermenting fort, of which the following is a specificatron.

This invention relates to improved means for fermenting wort within acycle of fermentingtubs, whereby the fermenting process is simplifiedand expedited and numerous other advantages hereinafter specified areobtained.

In the accompanying drawings, Figure 1 is a front view of an apparatusfor carrying my invention into effect, and Fig. 2 a longitudinal sectionof one of the tubs.

A series of fermenting-tubs 3 4 5 6 7 8 made, preferably, of wood orenameled steel are installed in the fermenting-cellar side by side, eachfermenting-tub being of sufficient size to accommodate the entire brewof one day. The tubs are of cylindrical form and are mounted on supports9 in a substantially horizontal position, having, however, a slightforward dip, as shown.

The front head 10 of each tub is provided with a manhole and cover 11and with one or two spring-valves 12, located at about onequarter theheight of the beer in the tub. It is further provided with one or twolower spring-valves 13, arranged slightly above the bottom, and with oneor more removable observation-glasses 14 above the liquid-level. Throughthe bottom of head 10 enters the aerating cook or nozzle 15 of acompressedair pipe 16, which projects into the forward end of aninclined tube 17. This tube is arranged longitudinally within the tubeand is open at both ends. The bottom of the tub is provided near itsforward end with a washout nipple 18.

The rearhead 19 may be provided with one or more spring-valves 20, thatcooperate with valves 13 for rapidly emptying the tub. A combinedair-inlet and gas-outlet nozzle 21, having coclr'22, connects with theupper rear end ofthe tub above the liquid-level.

The operation is as follows: The unfermented wort prepared on the firstday is run into tub 3 and pitched with yeast. After eighteen toforty-eight hours (depending upon the temperature of the beer and thequantity of yeast used) when the yeast has begun to grow and multiplytub 3 is half emptied into tub 4 through spring-valves 12 andhose-couplings 23. The wort prepared on the second day is then run intotub 3 and also into tub 4 to fill both tubs to about the level 24. Theyeast will thus again vigorously multiply and develop in the tubs. Afteragain eighteen to forty-eight hours tub 4 is half emptied into tub 5,and tubs 4 and 5 are filled up with the unfermented wort prepared on thethird day. This operation is continued successively for tubs 6, 7, and8, half of the fermented contents of the last tub being run into tub 3,which has previously been emptied, as hereinafter described. In this waya complete cycle is established, each tub serving to produce the beerfor one of the days of a week. Of course the number of tubs may bevaried according to the duration of the fermentation and the output ofthe brewery. After a tubsay tub 3has been half emptied of the fermentedliquid and filled up with fresh brew in the manner described the beer isaerated during the first two days by forcing pure air through nozzle 15into tube 17. The air should enter tube 17 under about twenty poundspressure, so that the tube acts similarly to an injector. The wort isthus drawn into the mouth of the tube, be comes mixed with the air, andescapes at the back of the tube. In this way there is created a livelycirculation of the wort and an intimate and uniform mixture of wort andair, thus producing perfect aeration of the beer. On the third andfourth days the cock 2- is opened to permit the carbonic-acid gasgenerated to escape, while during the last two days theobservation-glasses 14 are removed and the nipple 21 is coupled to apurified-air supply. Pure air is now forced through nipple 21 into thetub to pass over the surface of the beer, while the last carbonic-acidgas is ejected through the openings of the observation-glasses 14. Thefermentation being now completed, the tub is emptied through valves 13and 20 and is washed out through nozzle 18 As the tub inclines from therear toward the front the yeast and the washing-water can be easilyremoved through this nozzle.

The contents of tub 4 are on the next day subjected to the treatmentdescribed, and so on through the entire series, so that each tubfurnishes the beer for one day of the week, as desired.

The advantages connected with my improved process are numerous. By theem is required.

ployment of horizontal tubs a practically unlimited quantityof beer canbe fermented at a time, which is not the case with vertical tubs,because with the latter the height of the beer column materially affectsthe fermentation and clarification. Horizontal tubs, on the other hand,can be built of any length desired, while the height may remain thesame. The wort, on account of its low level, is quickly fermented, thebeer clarifies more rapidly, and but a single pitching with yeast Aslong as no infection manifests itself the same yeast can be carriedalong for months and years. The best and most vigorous yeast only istransferred from tub to tub, owing to the location of valves 12 at onequarter the height of the beer-level.

The aeration of the wort is exceedingly intense and uniform, insuring aquick start and vigorous development of the fermentation and keeping theyeast' pure. As the wort runs from one tub into another by gravity, allpumping is done away with, and the number of men required for duty inthe fermenting-cellar is reduced to a minimum.

What I claim is 1. Process for the continuous fermentation of wort bymeans of a battery of tubs, which consists in conveying part offermented wort successively from one tub to the next tub, and filling upthe partly-filled tubs with unfermented wort, substantially asspecified.

'mented wort in a tub by the addition of yeast,

drawing off part of the wort when fermented, filling up the tub withunfermented wort, to produce a new fermentation, aerating the beer,liberating the carb onic-acid gas evolved, and forcing air over thesurface of the beer,

substantially as specified.

4. A process of fermenting wort, which consists in effectingfermentation of unfermented wort successively in a cycle of tubs,discharging part of the fermented wort from one tub into the succeedingtub, filling up the partly-filled tubs with unfermented wort,

and successively subjecting the contents of the tubs to aeration and theaction of surface air, substantially as specified.

Signed by me at New York city, (Manhattan,) New York, this 12th day ofApril, 1906.

HERMANN A. SCHALK.

Witnesses:

GEORGE HINKEL, Jr., GEORGE E. RUPPERT.

